Automatic gun or rifle.



W. M. DOUGLAS.

AUTOMATIC GUN QR RIFLE.

APPLICATION FILED JUNEfzo 191 Patented May 7, 1912.

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W. M. DOUGLAS. AUTOMATIC GUN OR RIFLE.

APPLICATION FILED JUNE so, 1911.

Patented May 7, 1912.

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APPLIUATION FILED JUNE ao, 1911.

Patented May 7, 1912.

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Patented May E912.

W. M. DOUGLAS. AUTOMATIC GUN OR RFLE. APPLICATION FILED JUNEso, 1911,

WILLIAM M. DOUGLAS, F GALVESTON, TEXAS.

AUTOMATIC GUN OB RIFLE.

`Specification of Letters Patent.

Patented May 7, 1912.

Application filed June 30, 1911. Serial No. 636,248.

To all whom it may concern:

Be it known that I, WILLIAM M. DOUGLAS, a citizen of the United States,residing at Galveston. in the county of Galveston and State of Texas,have invented certain new and useful Improvements in IAutomatic Guns orRides, of which the following is a specilication.

This invention relates to tire arms and has particular reference to anautomatic g'un or rifle.

An important object- 'of this invention is to provide a magazine gun orrifle, which is automatically operated to eject the tired cartridges andreloaded, by utilizing a portion of the pressure from the explodingshell or cartridge.

A further object of this invention is to provide a gun or rifle of theabove 4mentioned character, which is quick in action, easy and automaticin operation, and not liable to derangements.

Gther objects and advantages of this invention will be apparent duringthe course' of the following description.

In the accompanying drawings forming a part of this specii'ication andin which like numerals are employed to designate like` parts throughoutthe same, Figure 1 is a longitudinal sectional view 'taken through themagazine and associated members, Fig. 2 is a plan view of that portionof the gun or rifle shown in Fig. 1, Fig. 3 is a side view of the outerend of the barrel of the gun or rifie, shown partly in section, togetherwith associated members shown in section. Fig. f1 is a side view of thegas-plunger, Fig. 5 is a cross-sectional view taken on line 5-5 of Fig.3, Fig. 6 is a longitudinal sectional view taken through the aircompressing cylinder, F ig. 7 is a longitudinal sectional view takenthrough the breech-bolt and associated members, Fig. 8 is a fragmentaryside view of the stock of the gun or riie, showing the hammer, magazineand associated members, Fig. 9 is a transverse sectional view taken online 9 9 of Fig. 8, Fig. 10 is a longitudinal sectional view takenthrough the rear portion of the stolpk and showing the breechboltoperating cy inder and associated members, Fig. 11 is atransversesectional view taken on line 11H11. of Fig. 2, Fig. 12 is an end View ofthe breech-bolt, removed, and, Fig. 13 is a detail showin the ejector,In the drawings wherein is illustrated a preferred embodiment of myinvention, the

'numeral 1 designates the barrel of the gun or rie, which is disposedupon a forearm 2 of the usual stock. The barrel 1 is attached tothe forearm by bands 3 and 4, shown in Figs. 3 and 6. At the outer end thebarrel 1 carries a vsight 5 and a sword-bayonet 6 is secured to theouter end of the barrel 1 vin the usual manner. nally through theforearm 2 is a gas-pipe or cylinder 7, having communication with thebarrel 1 through a port 8, which is disposed near and spaced from theouter end of the barrel. A sleeve 9 connects the gas pipe 7 and thebarrel 1, the port 8 .passing through a portion of this sleeve. thegas-pipe 7 is internally screw-threaded for receiving an externallyscrew-threaded plug 10, which is locked against rotation by a cap 11having screw-threaded engagement therewith and with an extension formedVupon the outer end of the gas-pipe 7. Disposed within theforwardportion of the gas-pipe 7 is a gas-plunger 1,2 adapted to reciprocatetherein and provided upon its periphery with annular grooves forreceiving packing rings 13. The gas-plunger 12 has one end formed closedand is provided with an aXialopening 14 which extends through theopposite end of the plunger. The gas-pipe 7 extends rearwardly throughthe forearm 2 and terminates nearthe rear band 4, as shown in Fig. 6.The rear end Extending longitudi- The outer end ofI of the gas-pipe iitswithin or telescopes an air compressing cylinder 15, within which 1smounted to reciprocate an air compressing piston 16, having annulargrooves,-

formed upon its periphery for receiving packing rings 17. A cylinder 18is interposed between the gas-pipe 7 and the air compressing piston 16and is rigidly held against movement. The cylinder 18 is providedcentrally thereof with an opening for receiving areciprocatory rigid rod19, having its rear end attached'to the air compressing piston 16 andits forward end attached to the gas-piston 12. A compressible coilspring 20 surrounds the rod 19 and is confined between the gas-piston 12and the stationary cylinder 18. At the rear end of the air compressingcylinder 15 is a reducing pipe or conduit .21, having connection withtwo branch pipes or conduits los 22 and 23. The pipe 22 continueslongitudinally of the forearm and leads 'into the forward end of abreech holtcylinder 24, as more clear y shown in Figs. 10 and 2. Thebranch pipe 23 extends transversely ofthe toi-carin 2 and leads into acompressed air Vpipe 25, which is disposed upon the right Mside ot thebarrel 1, see Figs. 6 and 2. Connected with the rear end of thecompressed air pipe 25 is an upstanding nozzle 26, as more Aclearlyshown in Fig. 9. Disposed within the breech-bolt cylinder 2st is apiston 27, slidably mounted therein and carrying a curved arm 2S, whichoperates within an elongated slot 29. The rearward morement ot' thepiston 27 is opposed by a. compressible coil spring 30 disposed withinthe breech-bolt cylinder 24 and held therein by a plug or cap 31 whichcloses the rear end of the cylinder 29. The plug or cap 29 hasscrew-threaded engagement with the cylinder 24 and is clamped or lockedagainst accidental rotation by a locking ring 32, having screw-threadedengagement with the cylinder 24, -as shown in Fig. 10.

The numeral 33 designates a maga-zine for holding a plurality of shellsor cartridges S4 in superposed horizontal positions. A spring placed inthe bottom of the magazine serves to .more the cartridges upwardly, whenthe gun or ritie is being reloaded. Disposed above the magazine 33 is asliding breech-bolt 36, disposed within a track or housing comprisingside walls 3T. The upper side of this housing is normally closed by aslide cover 38. The arm 2S operates within a longitudinal opening 29 andis rigidly attached Ito the breech-bolt 36. This breech-bolt ispreferably formed square in cross-section and is provided with. acylindrical axial opening formed' thereinv tor receiving alocking-cylinder Ll0. This lool:- ing-cylinder is capable of turningwithin the breech-bolt 36 but cannot have any perceptible longitudinalmovementtherein. As shown in Fig. 7,A the locking cylinder Ll() isprovided with a longitudinal opening 4:1 for receiving a tiring pin 42extending into 'a larger longitudinal opening 48 Jformed through thelocking cylinder. Mounted to reciprocate within the opening 43 is aplunger 44 attached to the tiring pin l2 and carrying a stop 45,disposed for movement. within a slot 46. Surrounding a portion of thetiring pin 42 is a compressible coil spring 46 confined between the endwall of the opening Li3 and one end of the plunger 44. The lockingcylinder' 40 is provided at one end with an enlarged cylindrical headLil", carrying inteirupted screw-threads 48 upon its periphery, adaptedfor detachable engagement with corresponding screw-threads 49 formed onthe wall olf the bore ot' the barrel 1 and at the rear end of thebarrel. as clearly shown in Figs. l and 2. The

Ilbreech-bolt has an extractor 50 rigidly attached. to the forward endthereof, .which is Lacasse adapted to engage the flange 51 of acartridge 52. The bore of the barrel lis counter-bored slightly7 asshown at 53 to receive the cartridge.

The breech-bolt 3B is provided near its forward end. and upon its uppertace with a transverse opening 54, for receiving a downwardly curvedhandle-bar 55 which is rigidly connected with the locking cylinder l0.This handle-bar 55 is adapted to travel vwithin a longitudinal slot 56when movedY vertically out of an enlargement 57, which is disposed at.the forward end of the slot 56. The curved' handle-bar when thebreech-bolt 36 is in its most 'forward position, is disposed directlyabove the com! pressed air nozzle 2G. A leaf-spring 5S is attached tothe breech-bolt and permanent-ly engages Ythe handle-bar 55 to swing thesame downwardly. The housing is provided near its upper edee with adischarge opening 59 and upon its opposite wail with a pivoted ejectorG0, which is automatically moved by a spring 6l. y

Disposed to the rear of the magazine is ,a hammer 62 pivoted as shown at63 in the small of the'stoclr and adapted to'strike the plunger 411.This hammer'is operated by a main spring 64 and is normally held againstmovement by a trigger 65, pivoted shown at 65 and engaged by a'triggerspring G7. A pivoted cap G8 is adapted to be swung between theplunger 4:4 and the hammer G3, to avoid accidents.

The numeral 69 designates a triggerguard andthe numeral 70 designates arear sight', which may be of any well known or preferred type.

In the operation of my 0am or rifle, assuming that the same is loadedand that the different parts occupy the position shown in Fig. l, theoperator cocks thehammen 62 and swings cap 68 from betwee, fthe hammerand the plunger 44. lVhe?;.the trigger is pulled the hammer strikes theplunger 44 and the cartridge 52.is.tred. Then the bullet of thecartridge passs 'port 8 and before itleaves the barrel 1, the gasesunder high pressure from the explosion pass through said port 8 intokthe gas .cylinder 7. The gas-piston 12 is now moved .rearwardly carryingwith it the rod 19,

which moves the air compressing plunger 1G rearwardly. By forming thegas-piston 12 with the axial opening ll:` the gases pass into such axialopening and expand the cylinder 12 whereby it always fits very snuglywithin the cylinder 7 and hence the gas can not pass the same. The airis now compressed within the cylinder 15 and part of this compressed airtravels through the pipe 22 and the other part through pipe 23 and intopipe 25. The compressedair is now discharged from the nozzle 26 and byimpinging against the handle-bar 55 elevates the same out of the enlarement 57 of the slot 56. This movement of the handle-bar turns thelocking-cylinder 40, whereby its screwthreaded head 47 disengagesscrew-threads 49. As soon as the locking-cylinder 40 is thus released,the compressed air acting upon the piston 27 will move the same to therear, whereby the breech-bolt 36 is also moved to the rear.l Thebreech-bolt by means of the extractor 50 carries the lired cartridge 52to the rear and positions the same opposite. the discharge opening 59,at which time the automatic ejector 60 operates to throwthe firedcartridge 52 out of the magazine through the opening 59. In its rearwardmovement the breech-bolt 36 cocks the hammer 62. As'soon as the firedcartridge 52 is discharged from the magav zine, spring 35 will elevatethe cartridcres to position the uppermost one forwar ly of and inalinement with the breech-bolt 36. lVhen the breech-bolt is movedforwardly and returned to the position shown in Fig. l, itforces theuppermost cartridge 34 into the counter-bore 53 and hence the gun isreloaded. This forward movement of the breech-bolt 36 is permitted bythe decrease in pressure in the cylinder 24, which takes place after thebullet has left the barrel 1, when the spring 30 forces the piston 27forwardly, which through the medium of the arm 28 returns thebreech-bolt- 36 to its most forward position. As soon as the breech-bolt36 is thus returned to its forward position, the handle-bar `55 will bedisposed in alinement with the enlargement 57, at which time the spring58 will automatically swing the vhandle-bar downwardly, whereby thelocking cylinder 40 is turned and its screw-threads 48 brought intoholding engagement with the screw-threads 49. When the operator againpulls thertrigger the above described operation is repeated.

I have found that particularly good results can be obtained by employingcartridges having bullets provided with axial openings formed therein,in order that the gases from the explosion may enter the bullet andexpand the same in the same manner as described in connection with mygaspiston,12. This will slightly retard the movement of the bullet inthe barrel 1 and hence increase the pressure in the barrel and thesupply of such pressure through-the port 8. I do not wish to restrictmyself to the employment of lsuch cartridges as my gun operatessatisfactorily with the ordinary cartridge having a solid bullet. t l

I wish it understood that the form of my invention herewith shown' anddescribed is,

sorted to without ,departing from the spirit" of the invention or thescope of the subjoined claims. i

Having thus described my invention, I claimtl. In a lirearm of thecharacter described, a. barrel, a magazine for holding a plurality ofcartridges to be fed intothe barrel, a breech-bolt, an element to lockthe breech-bolt in its closed position, compressed air operated means toactuate the element to release the breech-bolt, compressed air operatedmeans to move the breechbolt after it is unlocked, air compressingmechanism to supply compressed air tothe firstland second namedcompressed air operated means, a gas-cylinder having communication withthe barrel and receiving gas therefrom on discharge, a gas-piston oper-Aating in the gas-cylinder and actuatinglsaid air compressing mechanism,means to re- ,turn the breech-bolt to its closedi position,

means to ret-urn said element to its normalv gas therefrom on discharge,a piston operating within the gas-cylinder, an air compressing cylirder,a plunger operating within said air compressing cylinder, meansconnect-ing the piston and plunger, a breechbolt carrying an extractorand coperating with the barrel, an element for locking-the breech-boltin its clos-ed position, mechanism actuated by compressed air from theair compressing cylinder for operating said element, and means actuatedby such compressed air for moving the breech-bolt after the same isunlocked.

.3. In a fire arm of the character described, a barrel, a gas cylinderhaving communication with the barrel and receiving gas therefrom ondischarge, a piston operating within the gas-cylinder, air compressingmechanism operated by said piston, a breech-bolt, an arm connected withthe breech-bolt and carrying a piston, acylinder within which the lastnamed piston operates, means of communication between said aircompressing mechanism and th last named'cyl'inder,'a spring disposedWithin said last named cylinderto oppose the movement of the pistoncarried by the arm,

an element to lock the breech-bolt in its mechanism to said means andSecond named to return the piston to its normal position,

scribed, a barrel, e breech-holt carrying en extractor and cooperatingtherewith, a' loching element to hold thebrcech-bolt,against movementand carrying a handle bar, a nozzle disposed near the handle bur, andg elocking cylinder mounted within' the breech-bolt, an element to turn thelocking cylinder, means to move the element, mech- :mism to move thebreech-bolt after the sameA is unlocked, and conduits for supplyingcompressed air from said air compressing mechanism.

5. In a fire arm of the character described, a barrel, a gas-cylinderhaving communication therewith and receiving gas therefrom on discharge,a piston operating within the gas-cylinder, an air compressing cylinder,a plunger operating therein, a rod connecting the piston and plunger, aspring a breech-bolt, an arm connected with the breech-boltand carrying.a piston, a cylinder Within which the arm piston operates, e spring toreturn the arm piston to its normal position, means of communicationbetween the air compressing cylinder and the last named cylinder, alocking element for normolly holding the breech-bolt in its closedposition, a nozzle for conducting air to move the locking element, andmeans of communication between the nozzle and said air compressingcylinder.

6. In a lire arm of the character desuresnes means to supply compressedI air tothe nozzle. Y,

7. In e lire arm of the character described, a barrel, a breech-boltcarrying an extractor and coperating therewith, a locking element tohold the breech-bolt against 40 movement and carrying a handle bar, anozzle disposed near the handle bar, means for moving the breech-boltincluding a. cylinder and piston operating` therein, and

means for supplying the compressed air to the nozzle and said cylinder.A

8. In al fire arm of the character de? scribed, a barrel, ureciprocatory breech-bolt disposed near the loading end of the barreland provided with an extractor, an element to normally lock thebreech-bolt in its closed position, Ymeans to operate the element torelease the breech-bolt, air compressing mechanism operated upon thedischarge of the firearm, means of communication bctween the rst namedmeans and said 1nech\ anism, means including a piston to move thebreech-bolt after 1t is released and operated by the an' compressingmechanism, and

vmeans for firing the cartridge including an 0 element disposed to heautomatically.cocked by the movement of the breech-bolt.

In testimony Whereol` I aliix my signature in presence of two witnesses.

VILLIAM M. DOUGLA? llritnesses J. FRAGUI, S. E. Downes.

